Is there any issues with removing the cat on a 130PD?

Will the turbo overspool or will it be fine as is?

As does it have to have a re map after or will it be fine left alone?

Been fine on the Fabia vRS for the last 20K+ miles running std map.

heard it dont really do to much for performance on a diesel

heard it dont really do to much for performance on a diesel

12bhp & 24lbft extra makes a difference from a full miltek and decat pipe running a generic map and panel filter on a pd130 octavia, the generic map was done a couple of years prior to the miltek and I didn't get the mapp tweaked afterwards and all was fine, it wasn't a smooth as it could be but I had no complaints, the toque rush was amazing and very adictive

The blue line is pre miltek

Turbo spools up so much quicker and earlier and a bit more turbo noise too think I did 15,000/20,000 miles with my miltek and no problems from it or turbo failure.

Edited 27 February, 201016 yr by matt@theforce

Ive not had mine custom re-mapped due to the clutch not being uprated so i wont try and get the most out of it!

I just know that a cat is a big restricion is the exhaust and just wondered is tehre was any issues with removing it

But now i know ill take the thing out

better spool up and i gained about 5mpg when i decatted my old 110tdi, also was 120bhp from just induction kit and the exhaust and well up on torque

To be fair a custom map on a non uprated clutch will be better than a generic map as you can have the map tweeked to provide a nice smooth curve and power delivery.

My generic map was quite aggresive and as such melted my oem clutch within a week.

To be fair a custom map on a non uprated clutch will be better than a generic map as you can have the map tweeked to provide a nice smooth curve and power delivery.

My generic map was quite aggresive and as such melted my oem clutch within a week.

Yeah ok it will be better but it will also give me more BHP and more torgue, which is what everyones after but not aon a standard clutch!! untill i get it changed ill leave mine as is, its nice and smooth and torguey enough for now

Whats the legalities of removing the cat?

I know the car doesnt really need it as the emmission test for my M3 was the same without as with but whats it like on a diesel?

And what if i was to put a cat bypass in, would that fail the MOT as the tester can clearly see that the cat has been removed!!

Edited 1 March, 201016 yr by dannyboy759

Good question... I might consider a decat or bypass if:

- I did not need to tell the insurance company

- it was legal

- my old oil burner could still pass an MOT!

Whats the legalities of removing the cat?

I know the car doesnt really need it as the imission test for my M£ was the same without as with but whats it like on a diesel?

And what if i was to put a cat bypass in, would that fail the MOT as the tester can clearly see that the cat has been removed!!

I was told when I bought my exhaust that cat's weren't needed on tdi's for MOT's, which was my big concern so I took the risk and my cat went from looking like this

to this

mmmm shiney

To be honest I'm not sure if the car will pass the MOT as I no longer own it but it is due for its MOT around now, I'll try and get in touch with the new owner and see if he has had any trouble with the MOT.

I've spoken to the new owner and he informs me that his octi flew through its MOT last week so NO cat is required for MOTs

Thanks for this info Matt, you went above and beyond!

I hope to get mine done soon, has been on the cards for a long while. Just a matter of money. Should get a quote really!!

Fabia vrs running a de cat for 4k and no issues what so ever

Turbo spools quicker and through my exhaust sounds awesome! Turbos hate back pressure so removing the cat and any boxes in the exhaust and running it straight through is the best option for a turbo. It's by far the second best thing I've done after my remap

Anyone know is the rough cost of decatting a TDi is?

£80 from a place in basingstoke

Fabia vrs running a de cat for 4k and no issues what so ever

Turbo spools quicker and through my exhaust sounds awesome! Turbos hate back pressure so removing the cat and any boxes in the exhaust and running it straight through is the best option for a turbo. It's by far the second best thing I've done after my remap

So you have no silencer?Backbox on your exhaust at all, or is it just the standard one?

And can anyone confirm this? (I was told when I bought my exhaust that cat's weren't needed on tdi's for MOT's, which was my big concern so I took the risk and my cat went from looking like this)

Edited 1 March, 201016 yr by dannyboy759

I have nothing but a 6x3 Oval tail pipe, absolutely no boxes from the turbo back

It sounds brilliant, i love it

A Diesel doesn't require a cat to pass an MOT as the Cat is only fitted to bring it inline with emissions regulations at the time of manufacture. After that it's not neccessary. Diesels undergo a smoke opacity test so no probe up the exhaust

I have nothing but a 6x3 Oval tail pipe, absolutely no boxes from the turbo back

It sounds brilliant, i love it

A Diesel doesn't require a cat to pass an MOT as the Cat is only fitted to bring it inline with emissions regulations at the time of manufacture. After that it's not neccessary. Diesels undergo a smoke opacity test so no probe up the exhaust

So just a tail pipe! would be interested to see some pics of that, just to see hopw you done it!

And ive been reading about the CAT thing! and no car is required by law to have one providing it goes through the emissions test ok plus why would a car need a cat when its got a closed loop lambda sytems that controls everything anyway!

The only emissions test that is done for diesels on the mot is the smoke test, the cat or lack of it will not affect this test. I previously had a diesel rover that went through 3 mot's with the cat innards missing. The legalities are down to insurance as you will have altered the car from standard, so this may give the insurance company a get out clause if they find the cat missing and you have to make a claim. Also make sure any decat pipe is at least the same diameter as the original exhaust as this can cause the turbo to fail.

You may also find the boost preasure has increased, dont know what the rated safe preasure is on the turbos used in the skodas, but going too high would have the obvious failure consequenses.

You should find as previously stated it will spool up earlier and quicker, also an increase in torque, hp and noise.

If you have access to a welder or someone that can weld it may be worth cutting the original cat off, knocking out the innards with a chisel then having it welded up. Sounds a bit primative, but it should work out less expensive than a decat pipe, if the weld is good theres less chance of it being discovered by the insurance company in the event of a claim, and you dont have to worry about the pipe internal diameter.

The VRS' don't have lambda sensors. Not sure whether all diesels don't have them or not?

It's just pipe mate, theirs nothing fancy involved at all. Remove the cat at the flexi section and get a custom exhaust made from their back

Heres a pic of my tail pipe, personally i think i need a bigger oval like a 6x4 or something but it does

Looks nice, i like the rear skirt

Looks nice, i like the rear skirt

Just noticed its a Fabia lol silly me!! thought it was an Octy

Lol